Salts of phosphonic acids

ABSTRACT

New and valuable salts of phosphonic acids whose cationic components are ammonium radicals, agents for influencing the growth of plants with these salts, and a process for their manufacture.

This is a division of application Ser. No. 568,147 filed Apr. 14, 1975, now U.S. Pat. No. 4,071,551.

The present invention relates to new salts of phosphonic acids whose cationic components are ammonium radicals, agents containing these salts for influencing plant growth, and a process for producing these compounds.

It is known that phosphonic acids (Dutch Pat. No. 1,668,075, German LaidOpen Application DOS 1,916,147) and ammonium salts (U.S. Pat. No. 3,230,069, Dutch Application No. 6,516,589 and French Pat. No. 1,461,144) have an influence on plant growth.

We have now found that salts of phosphonic acids of the formula ##STR1## where X denotes sulfur or oxygen, R¹ denotes linear or branched alkyl, alkenyl or alkynyl of 1 to 12 carbon atoms which may be substituted by 1 or more halogen atoms, or benzyl or naphthyl which may be substituted by one or more halogen atoms, amino, alkylamino, dialkylamino or nitro groups, and R² and R³ denote, independently of each other, hydrogen, alkyl of a maximum of 12 carbon atoms which may be substituted by halogen and at least one of R² and R³ denotes a radical of the formula ##STR2## where R⁴ denotes alkyl of a maximum of 6 carbon atoms or amino, and R⁵, R⁶ and R⁷, independently of each other, denote hydrogen, linear or branched, cyclic or non-cyclic alkyl, alkenyl or alkynyl of a maximum of 12 carbon atoms which may be substituted by one or more halogen atoms, oxirane or oxiranealkyl of a maximum of 6 carbon atoms, or R⁶ and R⁷ together form a heterocyclic ring, e.g., pyrrolidione, piperidine, morpholine, hexahydropyridazine and tetrahydropyridazine, have a powerful effect on plant growth.

The action of the new active ingredient is similar to that of quaternary nitrogen compounds and various phosphonic acid derivatives. However, at the same application rates the action of the new compounds is generally much more marked, quite apart from the fact that the spectrum of action is much broader. Plant growth responses caused by the compounds of the invention are in particular the following:

Reduction of stem or stalk length, thus increasing the resistance to lodging of barley, oats, rye, wheat, Indian corn, soybeans and cotton.

Abscission of foliage, flowers and fruit, e.g., in olives and tree nursery plants.

Promotion of ripening, for instance in tomatoes, citrus fruits and bananas.

Increase in yield, particularly in cereals and legumes.

The new active ingredients may be applied to the foliage and stems of the plants, and to the soil in which the plants are growing, or as seed dressings; they are in all cases effective, regardless of the application method employed. It is also possible to combine the compounds of the invention with other active ingredients, especially plant protection agents, and fertilizers and inert carriers. The addition of wetting agents usually fortifies the action.

The new salts according to the invention may for instance be prepared as follows: ##STR3## R¹, R², R³, R⁴, R⁵, R⁶ and R⁷ have the above meanings, Hal denotes halogen and Me stands for a metal atom, e.g., alkali metal, alkaline earth metal or an ammonium ion.

The hydrogen halide liberated in the above reactions may be removed from the reaction mixture for instance by introducing gases, e.g., nitrogen, oxygen, and carbon dioxide, by conventional acid binding agents, e.g., amines, especially tertiary amines such as triethylamine, or by employing metal hydroxides (e.g., alkali metal hydroxides and alkaline earth metal hydroxides), metal carbonates, metal hydrogen carbonates, alcoholates, and ammonium or metal salts of phosphonic acids.

The reaction of free phosphonic acid with a substituted ammonium halide is preferred.

The above reactions are advantageously carried out in diluents, the following being suitable examples: alcohols, e.g., methanol, ethanol and propanol; nitriles such as acetonitrile and propionitrile; ketones, e.g., acetone and methyl ethyl ketone; water, benzene, toluene, chlorobenzene, xylenes, chlorinated hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride; dimethyl sulfoxide, dimethylformamide and other solvents. Most suitable are solvents enabling the desired phosphonic acid salt to be separated direct from any inorganic reaction products which may be obtained, e.g., alcohols, ketones and nitriles.

The reactions may be carried out over a wide temperature range of from -10° C. to the decomposition point of the reactants and end products (+250° C.).

The preparation of the compounds of the invention is illustrated by the following examples. The salts are identified by their nmr spectra.

EXAMPLE 1 ##STR4##

At 50° C., 5.6 parts (by weight) of potassium hydroxide in 50 parts of ethyl alcohol was added to a solution of 14.4 parts of 2-chloroethanephosphonic acid and 15.7 parts of chlorocholine chloride in 100 parts of ethyl alcohol. The mixture was stirred for 3 hours at 70° C. and then cooled. The precipitate was separated by filtration. The filtrate was concentrated and recrystallized from a mixture of methanol and ligroin. The melting point was 86° to 87° C. and the yield 25.4 parts (95.5% of theory). C₇ H₁₈ Cl₂ NO₃ P (266)

    ______________________________________                                                  C     H       N       P     Cl                                        ______________________________________                                         Calc.:     31.6    6.8     5.3   11.6  26.7                                    Found:     31.2    6.5     5.0   11.7  26.3                                    ______________________________________                                    

nmr (δ values) at 60 mc/sec: 3.5-4.05 (6 H), 3.2 (9 H), 2.17 (2 H).

EXAMPLE 2 ##STR5##

At 20° C., 6.8 parts of sodium ethylate in 50 parts of ethanol was added to a solution of 10.8 parts of vinylphosphonic acid and 13.75 parts of isopropyl trimethylammonium chloride in 80 parts of ethanol. The mixture was then stirred for 5 hours at 70° C. and worked up as in Example 1. The yield was 19.9 parts (95% of theory). C₈ H₂₀ NPO₃ (209)

    ______________________________________                                                   C      H        N        P                                           ______________________________________                                         Calc.:      45.9     9.6      6.7    14.8                                      Found:      45.6     9.6      6.9    14.7                                      ______________________________________                                    

nmr (δ values) at 60 mc/sec: 5.2-6.25 (3 H), 3.62 (H), 3.02 (9 H), 1.36 (6 H).

EXAMPLE 5 ##STR6##

3.92 parts of potassium hydroxide in 50 parts of ethanol was added to a solution of 10.1 parts of 2-chloroethanephosphonic acid in 80 parts of ethanol. After the mixture had been stirred for 1 hour at 40° C. the solvent was distilled off. The residue was taken up in 150 parts of acetonitrile and 13.6 parts of N,N-dimethylpiperidinium bromide was added to the mixture. The reaction mixture was stirred for 5 hours at 70° C. and then cooled. The precipitates was filtered off and the filtrate concentrated. The yield was 17.5 parts (97% of theory).

    ______________________________________                                         C.sub.9 H.sub.21 NPO.sub.3 Cl (257.5)                                                   C     H       N       P     Cl                                        ______________________________________                                         Calc.:     42.0    8.2     5.4   12.1  13.8                                    Found:     41.8    8.1     5.5   12.4  13.9                                    ______________________________________                                    

nmr spectra (δ values) at 60 mc/sec: 3.77 (2H), 3.32 (4H), 3.09 (6H), 2.14 (2H), 1.6-1.95 (4H), 1.7 (2H).

The following salts were prepared in similar manner:

    __________________________________________________________________________      ##STR7##                                                                                              ##STR8##        nmr spectra (δ values) at                                                60 me/sec 1.4 (6 H), 2.16 (2 H) ,                                              .04 (9 H) , 3.4-4.0 (3 H)               ##STR9##                                                                                              ##STR10##       6.1 (2 H), 4.02 (2 H), 3.77 (2                                                 H), 3.24 (9 H)                          ##STR11##                                                                                             ##STR12##       2.19 (2 H), 3.24 (18 H), 3.7-3.87                                              (6 H), 3.97-4.16 (4 H)                  ##STR13##                                                                                             ##STR14##       characteristic infrared bands                                                  (cm.sup.-1) 1650, 1475, 1180,                                                  1100, 1050, 920, 530                    ##STR15##                                                                                             ##STR16##       2.18 (2 H), 3.28 (6 H), 3.5 (4                                                 H), 3.78 (2 H), 3.95-4.18 (4 H)         ##STR17##                                                                                             ##STR18##       3.3-4.2 (10 H), 3.09 (9 H), 2.05                                               (2 H)                                   ##STR19##                                                                                             ##STR20##       characteristic infrared bands                                                  (cm.sup.-1) 1650, 1475, 1150,                                                  1050, 945, 915, 775, 490                ##STR21##                                                                                             ##STR22##       characteristic infrared bands                                                  (cm.sup.-1) 1640, 1480, 1185,                                                  1160, 1050, 940, 910, 530               ##STR23##                                                                                             ##STR24##       5.6-6.3 (3 H), 3.23 (9 H), 4.02                                                (2 H), 3.82 (2 H)                       ##STR25##                                                                                             ##STR26##       1.72 (2 H), 2.02 (2 H), 2.19 (2                                                H), 3.18 (2 H), 3.34 (6 H), 3.52                                               (2 H), 3.78 (2 H)                       ##STR27##                                                                                             ##STR28##       2.21 (2 H), 3.45 (6 H), 3.79 (2                                                H), 3.9-4.1 (4 H)                       ##STR29##                                                                                             ##STR30##                                               ##STR31##                                                                                             ##STR32##                                               ##STR33##                                                                                             ##STR34##                                               ##STR35##                                                                                             ##STR36##                                               ##STR37##                                                                                             ##STR38##                                               ##STR39##                                                                                             ##STR40##                                               ##STR41##                                                                                             ##STR42##                                              __________________________________________________________________________

the growth-regulating properties of the compounds according to the invention may be extended by adding other growth regulators and adapted to suit prevailing conditions by mixing them with fungicides and fertilizers, especially urea. The ratio of the salts of the invention to growth regulators, fungicides and fertilizers in such compositions may be varied at will; what type of composition is used depends on the conditions encountered (fungus diseases, deficiencies, etc.).

Examples of growth regulators which may be mixed with the salts of the invention are:

phosphonic acids and their derivatives, such as

2-chloroethanephosphonic acid

vinylphosphonic acid

propylphosphonic acid

phosphonomethylglycine

bisphosphonomethylglycine

benzylphosphonic acid

ammonium and hydrazinium salts, such as

chlorocholine hydrochloride

N,n-dimethylmorpholinium halide

N,n-dimethyl-N-2-chlorpethylhydrazinium halide

N,n-dimethyl-N-2-bromoethylhydrazinium halide

N,n-dimethyl-N-isopropylhydrazinium halide

N,n-dimethyl-N-propen-(2)-ylhydrazinium halide

N,n,n-trimethyl-N-cyclopropanemethylammonium halide

N,n-dimethylhexahydropyridazinium halide

N,n-dimethyltetrahydropyridazinium halide

N,n,n-trimethyl-N-cyclopentenylammonium halide

N,n-dimethyl-N-cyclopentenylhydrazinium halide

N,n,n-trimethyl-N-isopropylammonium halide

carboxylic acid and derivatives thereof, such as

β-indolylacetic acid

α-naphthylacetic acid

4-chlorophenoxyacetic acid

2,4-dichlorophenoxyacetic acid

2-methyl-4-chlorophenoxyacetic acid

2,4,5-trichlorophenoxyacetic acid

α-(2-methylphenoxy)-propionic acid

α-(2,4-dichlorophenoxy)-propionic acid

α-(2-methyl-4-chlorophenoxy)-propionic acid

α-(2,4,5-trichlorophenoxy)-propionic acid

γ-(2,4-dichlorophenoxyl-butyric acid

γ-(2-methyl-4-chlorophenoxy)-butyric acid

2,4,5-triiodobenzoic acid

sulfonium salts, such as

S,s-dimethyl-S-2-chloroethylsulfonium halide

S,s-dimethyl-S-isopropylsulfonium halide

S-methylthianium halide

1-methyl-1,4-dithianium halide

heterocyclic structures, such as

maleic hydrazide

succinic acid-N,N-dimethylhydrazide

N-formyl-N-hydroxyglycine and salts

9-hydroxyfluorene-9-carboxylic acid

7-chloro-9-hydroxyfluorene-9-carboxylic acid citric hydrazide

5-chloro-2-thienylmethyl tri-n-butylphosphonium halide

Examples of fungicides capable of combination with the compounds of the invention are

dithiocarbamates and derivatives thereof, e.g.,

ferric dimethyldithioacrbamate (ferbam)

zinc dimethyldithiocarbamate (ziram)

manganese ethylenebisdithiocarbamate (maneb)

zinc ethylenebisdithiocarbamate (zineb)

tetramethylthiuram disulfide (thiram)

3,5-dimethyl-1,3,5-2H-tetrahydrothiadiazine-2-thione

nitrophenol derivatives, such as

dinitro-(1-methylheptyl)-phenylcrotonate (dinocap)

2-sec-butyl-4,6-dinitrophenyl-3,5-dimethylacrylate (binapacryl)

2-sec-butyl-4,6-dinitrophenylisopropylcarbonate

heterocyclic structures, such as

N-trichloromethylthiotetrahydrophthalimide (captan)

N-trichloromethylthiophthalimide (folpet)

2-heptadecyl-2-imidazoline (glyodin)

2,4-dichloro-b-(o-chloroanilino)-s-triazine

diethylphthalimido thiophosphate

5-amino-1-[bis-(dimethylamino)-phosphynyl]-3-phenyl-1,2,4-triazole

5-ethoxy-3-trichloromethyl-1,2,4-thiadiazole

2,3-dicyano-1,4-dithiaanthraquinone (dithianon)

2-thio-1,3-dithio-[4,5-b]-quinoxaline (thioquinox)

methyl-1-(butylcarbamoyl)-2-benzimidazolecarbamate

2-methoxycarbonylaminobenzimidazole

2-thiocyanomethylthiobenzothiazole (busan)

4-(2-chlorophenylhydrazono)-3-methyl-5-isooxadolone

pyridine-2-thiol-1-oxide

8-hydroxyquinoline and its copper salt

2,3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin-4,4-dioxide

2,3-dihydro-5-carboxyanilido-6-methyl-1,4-oxathiin 5,5-dimetyyl-3-(3,5-dichlorophenyl)-2,4-dioxo-1,3-oxazolidine

2-[furyl-(2)]-benzimidazole

piperazine-1,4-diyl-bis[1-(2,2,2-trichloroethyl)-formamide]

2-[thiazolyl-(4)]-benzimidazole

5-butyl-2-dimethylamino-4-hydroxy-6-methylpyrimidine

bis-(p-chlorophenyl)-3-pyridinemethanol

1,2-bis-(3-ethoxycarbonyl-2-thioureido)-benzene (thiophanat)

1,2-bis-(3-methoxycarbonyl)-2-thioureido-benzene

and various fungicides, such as

dodecylguanidine acetate (dodine)

3-[2-(3,5-dimethyl-2-oxycyclohexyl)-2-hydroxyethyl]-glutarimide (cycloheximide)

hexachlorobenzene

2,5-dimethylfuran-3-carboxanilide

2,5-dimethylfuran-3-carboxylic acid cyclohexylamide

2-methylbenzanilide

2-iodobenzanilide

2,3-dihydro-6-methyl-1,4-oxathiin-5-carboxanilide

2,3-dihydro-4,4-dioxy-1,4-oxathiin-5-carboxanilide

2,6-dimethyl-N-tridecylmorpholine and salts thereof

2,6-dimethyl-N-cyclodecylmorpholine and salts thereof 2,3-dichloro-1,4-naphthoquinone

1,4-dichloro-2,5-dimethoxybenzene

p-dimethylaminobenzenediazosodium sulfonate

2-chloro-1-nitropropane

N-(1,1,2,2-tetrachloroethylthio)-tetrahydrophthalimide

N,n-dimethyl-N-phenyl-(N-fluorodichloromethylthio)-sulfamide

N-methyl-N-phenyl-(N'-fluorodichloromethylthio)-N'-methylsulfamide

polychloronitrobenzenes, such as pentachloronitrobenzene, methyl isothiocyanate, fungicidal antibiotics such as griseofulvin and kasugamycin, tetrafluorodichloroacetone, 1-phenylthio semicarbazide, Bordeaux mixture, nickel-containing compounds and sulfur manganese-zinc ethylenediamine-bisdithiocarbamate zinc-(N,N'-propylene-1,2-bisdithiocarbamate) ammonia complex of zinc-(N,N'-ethylene-bisdithiocarbamate) and N,N'-polyethylene-bis-(thiocarbamoyl)-disulfide ammonia complex of zinc-(N,N'-propylene-bisdithiocarbamate) and N,N'-polypropylene-bis-(thiocarbamoyl)-disulfide.

EXAMPLE 4 Action on cotton

Cotton plants grown in the greenhouse were sprayed at a growth height of from 10 to 12 cm with formulations of the active ingredients. The application rate was 6 mg per vessel, corresponding to 6 kg per hectare. 18 days later the growth was measured and the absolute and relative height compared with control plants was determined.

    ______________________________________                                                              Growth height                                                                    absolute relative                                       ______________________________________                                         Control                    29.5     100                                         ##STR43##                 28.0     94.9                                        ##STR44##                 19.0     64.4                                        ##STR45##                 17.3     58.6                                        ##STR46##                 22.3     75.6                                        ##STR47##                                                                                   ##STR48##    16.0     54.2                                       ______________________________________                                    

example 5 action on rye

Rye grains of the Petkuser variety were sowed in loamy sandy soil contained in pots. The active ingredients were applied in aqueous solution to the surface of the soil immediately after the grains had been sown in amounts of 3 mg per vessel, equivalent to 3 kg per hectare. The experiment was conducted in the greenhouse. The growth height after 24 days is apparent from the following table:

    __________________________________________________________________________                                 Growth height                                                                  absolute                                                                            relative                                      __________________________________________________________________________     Control                     30.5 100                                            ##STR49##                  30.0 98.4                                           ##STR50##                  30.0 98.4                                           ##STR51##                  26.0 85.2                                          __________________________________________________________________________

at an application rate of 12 mg/pot (= 12 kg/ha) and under otherwise the same conditions, the following action was observed:

    __________________________________________________________________________     Control                    28.9 100                                             ##STR52##                 27.0 93.0                                            ##STR53##                 29.0 100                                             ##STR54##                 24.5 85.0                                           __________________________________________________________________________

example 6 action on wheat

The active ingredients according to the invention were tested on wheat of the Opal variety under the same conditions as in Example 5. The application rate was 12 mg/pot (= 12 kg/ha). The stalks had the following lengths 21 days after sowing:

    __________________________________________________________________________                                 Growth height                                                                  absolute                                                                            relative                                      __________________________________________________________________________     Control                     35.3 100                                            ##STR55##                  26.0 73.7                                           ##STR56##                  29.5 83.6                                           ##STR57##                  23.5 66.6                                           ##STR58##                  23.5 66.6                                          __________________________________________________________________________

example 7 action on barley

Barley plants were grown in pots in the open with a controlled water supply, and sprayed in the 3- to 4-leaf stage with aqueous formulations of the active ingredients. The application rate was 3 kg/ha. The influence of the active ingredients on stalk length (up to ripeness) is apparent from the following table:

                         Growth height                                                                    absolute relative                                       ______________________________________                                         Control                 70.8    100                                             ##STR59##             65.7     93.5                                            ##STR60##             69.3     97.9                                            ##STR61##             70.5     99.6                                            ##STR62##             65.0     91.8                                           ______________________________________                                    

example 8 action on rye

Rye plants in the 3- to 4-leaf stage were sprayed under the same conditions as in Example 7 at application rates of 3 kg/ha. The results are given below:

    ______________________________________                                                              Stalk length                                                                     absolute relative                                       ______________________________________                                         Control                135.2    100                                             ##STR63##             127.7    94.5                                            ##STR64##             129.8    90.0                                            ##STR65##             128.2    94.8                                            ##STR66##             116.3    86.0                                            ##STR67##             120.7    89.3                                           ______________________________________                                    

example 9 action on Indian Corn

Indian corn plants were grown in pots under the same conditions as in Examples 7 and 8. The active ingredients were applied to the leaves at a plant height of from 20 to 24 cm and at a rate of 3 kg/ha. The growth height was measured after 7 weeks:

    ______________________________________                                                              Growth height                                                                    absolute relative                                       ______________________________________                                         Control                111.3    100                                             ##STR68##             108.5    97.5                                            ##STR69##             108.3    97.3                                            ##STR70##                                                                      ##STR71##              99.8    89.7                                            ##STR72##             102.3    91.9                                           ______________________________________                                    

example 10 action on oats

Oat plants were grown in loamy sandy soil contained in pots in a greenhouse. The plants were sprayed at a height of from 10 to 12 cm with the active ingredients at a rate corresponding to 6 kg/ha. The following results were obtained after 15 days:

    ______________________________________                                                              Growth height                                                                    absolute relative                                       ______________________________________                                         Control                 29.5    100                                             ##STR73##             24.5     83.1                                            ##STR74##                                                                      ##STR75##             23.5     79.7                                           ______________________________________                                    

example 11 action on cress

40 cress seeds for each experiment were placed on filter paper, which was then introduced into a beaker containing 20 ml of active ingredient formulation. After 4 days the length of the plants was measured and calculated in percent of the growth of the untreated control. The figure 100% denotes no stunting and 0% complete growth inhibition.

    ______________________________________                                                               Relative length                                                             Concen-          Roots +                                                       tration  Roots   shoot                                      ______________________________________                                         Control            --       100     100                                         ##STR76##         1/2 mmol.                                                                               40      42                                          ##STR77##         1/2 mmol.                                                                               100     101                                                           1 mmol.  91      94                                          ##STR78##         1/2mmol. 34      34                                          ##STR79##                                                                     ______________________________________                                    

example 12

the compounds of the invention were applied, under otherwise the same conditions, in a concentration of 200 ppm. The results are given below:

    __________________________________________________________________________                                 Relative length                                                                Roots                                                                              Roots + shoot                                  __________________________________________________________________________     Control                     100 100                                             ##STR80##                  84  90                                              ##STR81##                  38  34                                              ##STR82##                  38  34                                              ##STR83##                  88  89                                              ##STR84##                  34  30                                              ##STR85##                  24  28                                              ##STR86##                  54  63                                              ##STR87##                  38  39                                             __________________________________________________________________________ 

we claim:
 1. A salt of a phosphonic acid, said salt being selected from the group consisting of ##STR88##
 2. An agent for inhibiting plant growth, which agent contains, in aqueous solution, an effective amount of a salt as set forth in claim
 1. 